[v4] staging: rtl8192e: Fix signedness bug in rtllib_rx_assoc_resp()

[PATCH V4] staging: rtl8192e: Fix signedness bug in rtllib_rx_assoc_resp()

Posted by Haowen Bai 4 years ago

The rtllib_rx_assoc_resp() function has a signedness bug because it's
a declared as a u16 but it return -ENOMEM.  When you look at it more
closely it returns a mix of error codes including 0xcafe, -ENOMEM, and
a->status which is WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG.  This is a mess.

Clean it up to just return standard kernel error codes.  We can print
out the a->status before returning a regular error code.  The printks
in the caller need to be adjusted as well.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
---
V1->V2: reduce return random value; print its own error message.
V2->V3: change commit message; change s16 -> int.
V3->V4: 
1. change message suggested by Dan Carpenter;
2. hold a->status in auth_parse() and return error code or 0 on success.
3. print le16_to_cpu(errcode) -> int %d.

 drivers/staging/rtl8192e/rtllib_softmac.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/rtl8192e/rtllib_softmac.c b/drivers/staging/rtl8192e/rtllib_softmac.c
index 82bf05eb1cbf..38ac733c3245 100644
--- a/drivers/staging/rtl8192e/rtllib_softmac.c
+++ b/drivers/staging/rtl8192e/rtllib_softmac.c
@@ -1764,7 +1764,7 @@ static void rtllib_softmac_check_all_nets(struct rtllib_device *ieee)
 	spin_unlock_irqrestore(&ieee->lock, flags);
 }
 
-static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
+static inline int auth_parse(struct net_device *dev, struct sk_buff *skb,
 			     u8 **challenge, int *chlen)
 {
 	struct rtllib_authentication *a;
@@ -1773,7 +1773,7 @@ static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
 	if (skb->len <  (sizeof(struct rtllib_authentication) -
 	    sizeof(struct rtllib_info_element))) {
 		netdev_dbg(dev, "invalid len in auth resp: %d\n", skb->len);
-		return 0xcafe;
+		return -EINVAL;
 	}
 	*challenge = NULL;
 	a = (struct rtllib_authentication *) skb->data;
@@ -1787,7 +1787,13 @@ static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
 				return -ENOMEM;
 		}
 	}
-	return le16_to_cpu(a->status);
+
+	if (a->status) {
+		netdev_info(ieee->dev, "auth_parse() failed");
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
 static int auth_rq_parse(struct net_device *dev, struct sk_buff *skb, u8 *dest)
@@ -2282,7 +2288,7 @@ rtllib_rx_assoc_resp(struct rtllib_device *ieee, struct sk_buff *skb,
 
 static void rtllib_rx_auth_resp(struct rtllib_device *ieee, struct sk_buff *skb)
 {
-	u16 errcode;
+	int errcode;
 	u8 *challenge;
 	int chlen = 0;
 	bool bSupportNmode = true, bHalfSupportNmode = false;
@@ -2292,8 +2298,7 @@ static void rtllib_rx_auth_resp(struct rtllib_device *ieee, struct sk_buff *skb)
 	if (errcode) {
 		ieee->softmac_stats.rx_auth_rs_err++;
 		netdev_info(ieee->dev,
-			    "Authentication response status code 0x%x",
-			    errcode);
+			    "Authentication response status code %d", errcode);
 		rtllib_associate_abort(ieee);
 		return;
 	}
-- 
2.7.4

Re: [PATCH V4] staging: rtl8192e: Fix signedness bug in rtllib_rx_assoc_resp()

Posted by kernel test robot 4 years ago

Hi Haowen,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on v5.18-rc3]
[also build test ERROR on next-20220421]
[cannot apply to staging/staging-testing]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/intel-lab-lkp/linux/commits/Haowen-Bai/staging-rtl8192e-Fix-signedness-bug-in-rtllib_rx_assoc_resp/20220421-093531
base:    b2d229d4ddb17db541098b83524d901257e93845
config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20220421/202204211558.TapLZO4j-lkp@intel.com/config)
compiler: arceb-elf-gcc (GCC) 11.2.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/e1395cdafd4dea7a368f2d9599832636035a03d2
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Haowen-Bai/staging-rtl8192e-Fix-signedness-bug-in-rtllib_rx_assoc_resp/20220421-093531
        git checkout e1395cdafd4dea7a368f2d9599832636035a03d2
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross W=1 O=build_dir ARCH=arc SHELL=/bin/bash drivers/staging/rtl8192e/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   drivers/staging/rtl8192e/rtllib_softmac.c: In function 'auth_parse':
>> drivers/staging/rtl8192e/rtllib_softmac.c:1792:29: error: 'ieee' undeclared (first use in this function)
    1792 |                 netdev_info(ieee->dev, "auth_parse() failed");
         |                             ^~~~
   drivers/staging/rtl8192e/rtllib_softmac.c:1792:29: note: each undeclared identifier is reported only once for each function it appears in


vim +/ieee +1792 drivers/staging/rtl8192e/rtllib_softmac.c

  1766	
  1767	static inline int auth_parse(struct net_device *dev, struct sk_buff *skb,
  1768				     u8 **challenge, int *chlen)
  1769	{
  1770		struct rtllib_authentication *a;
  1771		u8 *t;
  1772	
  1773		if (skb->len <  (sizeof(struct rtllib_authentication) -
  1774		    sizeof(struct rtllib_info_element))) {
  1775			netdev_dbg(dev, "invalid len in auth resp: %d\n", skb->len);
  1776			return -EINVAL;
  1777		}
  1778		*challenge = NULL;
  1779		a = (struct rtllib_authentication *) skb->data;
  1780		if (skb->len > (sizeof(struct rtllib_authentication) + 3)) {
  1781			t = skb->data + sizeof(struct rtllib_authentication);
  1782	
  1783			if (*(t++) == MFIE_TYPE_CHALLENGE) {
  1784				*chlen = *(t++);
  1785				*challenge = kmemdup(t, *chlen, GFP_ATOMIC);
  1786				if (!*challenge)
  1787					return -ENOMEM;
  1788			}
  1789		}
  1790	
  1791		if (a->status) {
> 1792			netdev_info(ieee->dev, "auth_parse() failed");
  1793			return -EINVAL;
  1794		}
  1795	
  1796		return 0;
  1797	}
  1798	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp

[PATCH V5] staging: rtl8192e: Fix signedness bug in rtllib_rx_assoc_resp()

Posted by Haowen Bai 4 years ago

The rtllib_rx_assoc_resp() function has a signedness bug because it's
a declared as a u16 but it return -ENOMEM.  When you look at it more
closely it returns a mix of error codes including 0xcafe, -ENOMEM, and
a->status which is WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG.  This is a mess.

Clean it up to just return standard kernel error codes.  We can print
out the a->status before returning a regular error code.  The printks
in the caller need to be adjusted as well.

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
---
V1->V2: reduce return random value; print its own error message.
V2->V3: change commit message; change s16 -> int.
V3->V4: 
1. change message suggested by Dan Carpenter;
2. hold a->status in auth_parse() and return error code or 0 on success.
3. print le16_to_cpu(errcode) -> int %d.
V4->V5: fix compile error.

 drivers/staging/rtl8192e/rtllib_softmac.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/staging/rtl8192e/rtllib_softmac.c b/drivers/staging/rtl8192e/rtllib_softmac.c
index 82bf05eb1cbf..38ac733c3245 100644
--- a/drivers/staging/rtl8192e/rtllib_softmac.c
+++ b/drivers/staging/rtl8192e/rtllib_softmac.c
@@ -1764,7 +1764,7 @@ static void rtllib_softmac_check_all_nets(struct rtllib_device *ieee)
 	spin_unlock_irqrestore(&ieee->lock, flags);
 }
 
-static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
+static inline int auth_parse(struct net_device *dev, struct sk_buff *skb,
 			     u8 **challenge, int *chlen)
 {
 	struct rtllib_authentication *a;
@@ -1773,7 +1773,7 @@ static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
 	if (skb->len <  (sizeof(struct rtllib_authentication) -
 	    sizeof(struct rtllib_info_element))) {
 		netdev_dbg(dev, "invalid len in auth resp: %d\n", skb->len);
-		return 0xcafe;
+		return -EINVAL;
 	}
 	*challenge = NULL;
 	a = (struct rtllib_authentication *) skb->data;
@@ -1787,7 +1787,13 @@ static inline u16 auth_parse(struct net_device *dev, struct sk_buff *skb,
 				return -ENOMEM;
 		}
 	}
-	return le16_to_cpu(a->status);
+
+	if (a->status) {
+		netdev_dbg(dev, "auth_parse() failed\n");
+		return -EINVAL;
+	}
+
+	return 0;
 }
 
 static int auth_rq_parse(struct net_device *dev, struct sk_buff *skb, u8 *dest)
@@ -2282,7 +2288,7 @@ rtllib_rx_assoc_resp(struct rtllib_device *ieee, struct sk_buff *skb,
 
 static void rtllib_rx_auth_resp(struct rtllib_device *ieee, struct sk_buff *skb)
 {
-	u16 errcode;
+	int errcode;
 	u8 *challenge;
 	int chlen = 0;
 	bool bSupportNmode = true, bHalfSupportNmode = false;
@@ -2292,8 +2298,7 @@ static void rtllib_rx_auth_resp(struct rtllib_device *ieee, struct sk_buff *skb)
 	if (errcode) {
 		ieee->softmac_stats.rx_auth_rs_err++;
 		netdev_info(ieee->dev,
-			    "Authentication response status code 0x%x",
-			    errcode);
+			    "Authentication response status code %d", errcode);
 		rtllib_associate_abort(ieee);
 		return;
 	}
-- 
2.7.4

Re: [PATCH V5] staging: rtl8192e: Fix signedness bug in rtllib_rx_assoc_resp()

Posted by Dan Carpenter 4 years ago

On Thu, Apr 21, 2022 at 04:21:17PM +0800, Haowen Bai wrote:
> The rtllib_rx_assoc_resp() function has a signedness bug because it's
> a declared as a u16 but it return -ENOMEM.  When you look at it more
> closely it returns a mix of error codes including 0xcafe, -ENOMEM, and
> a->status which is WLAN_STATUS_NOT_SUPPORTED_AUTH_ALG.  This is a mess.
> 
> Clean it up to just return standard kernel error codes.  We can print
> out the a->status before returning a regular error code.  The printks
> in the caller need to be adjusted as well.
> 
> Signed-off-by: Haowen Bai <baihaowen@meizu.com>
> ---
> V1->V2: reduce return random value; print its own error message.
> V2->V3: change commit message; change s16 -> int.
> V3->V4: 
> 1. change message suggested by Dan Carpenter;
> 2. hold a->status in auth_parse() and return error code or 0 on success.
> 3. print le16_to_cpu(errcode) -> int %d.
> V4->V5: fix compile error.
> 

Looks ok.

Reviewed-by: Dan Carpenter <dan.carpenter@oracle.com>

regards,
dan carpenter